JPH11257141A - Common rail type fuel injection controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce driving torque in feeding of a variable displacement high- pressure pump without fluctuation of common rail pressure, in a common rail- type fuel injection controller. SOLUTION: A variable displacement high-pressure pump P reduces driving torque in feeding by being so constituted that the timings of increase or decrease of capacities of a plurality of pressure chambers may be staggered. Solenoid valves 6a, 6b for controlling the introducing amount of low-pressure fuel to the pressure chambers are provided to each pressure chamber, storage means 95a, 95b for storing the delay time from the time when a valve closing signal is output to the time when the solenoid valves 6a, 6b are closed are provided on a control means ECU, the output period of the valve closing signal is corrected on the basis of the stored delay time to prevent the actual introducing amount of low-pressure fuel from being varied between the solenoid valves 6a, 6b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a common rail type fuel injection control device for injecting high pressure fuel accumulated in a common rail (accumulation pipe) to each cylinder of a diesel engine by an electromagnetic fuel injection valve.

[0002]

2. Description of the Related Art There is a common rail type fuel injection control device as one of control devices for injecting fuel into a diesel engine. In the common rail fuel injection control device, a common pressure accumulation pipe (common rail) is provided for each cylinder of the diesel engine, and a variable discharge high pressure pump supplies high pressure fuel at a required flow rate under pressure to keep the common rail fuel pressure constant. Holding. The high-pressure fuel in the common rail is injected into each cylinder at a predetermined timing by an electromagnetic fuel injection valve.

FIG. 21 shows an example of a variable discharge high pressure pump constituting a common rail type fuel injection control device. A plunger 101 driven by a cam (not shown) is reciprocally fitted into a cylinder 100. The pressure chamber 102 is formed by the inner wall surface of the cylinder 100 and the upper end surface of the plunger 101. An electromagnetic valve 103 is mounted above the pressure chamber 102, and the electromagnetic valve 103 has a valve body 105 that opens and closes between a low-pressure flow path 104 formed therein and the pressure chamber 102.

The valve element 105 is in an open state in a state shown in FIG. 1 in which the coil 106 is not energized.
1, the low-pressure supply pump (not shown)
4. It is introduced into the pressure chamber 102 through a gap around the valve body 105. When the coil 106 is energized, the valve body 105 is attracted upward, and its substantially conical tip sits on the seat 107 to close the valve. At the same time, the fuel in the pressure chamber 102 is pressurized by the rise of the plunger 101, and is fed to the common rail by the flow path 109 provided on the side wall of the pressure chamber 102.

By the way, while the plunger 101 is rising,
Since a force in the valve closing direction acts on the valve body 105 by the fuel pressure of the pressure chamber 102, once the valve body 105 is closed, it does not open even if the energization of the coil 106 is stopped. For this reason, in the variable discharge high pressure pump having the above-described configuration, the flow rate sent to the common rail is controlled by so-called pre-stroke control that controls the valve closing timing. That is, the plunger 101
Does not close immediately after moving to the rising stroke,
By maintaining the valve open state until the fuel inside reaches a predetermined amount, excess fuel is released to the low-pressure flow path 104 side, and thereafter, the valve is closed and pressurization is started, so that the required amount of pressurized fluid is released. Feeding to common rail.

However, when the oil feed rate of the pump increases with an increase in the engine speed, there arises a problem that the valve body 105 closes (self-closes) regardless of the valve closing signal. This is because the lower end face of the valve body 105 directly receives the dynamic pressure of the fuel in the pressure chamber 102 when the plunger 101 is lifted, and the lower pressure passage 10 is smaller than the gap between the valve body 105 and the seat 107.
This is due to the effect of receiving a force in the valve closing direction due to the throttle effect of the fuel flowing to the fuel tank 4, and the flow rate control may not be properly performed.

As countermeasures against this, it is conceivable to increase the operating stroke of the valve body 105 or to increase the spring force of the return spring 108 of the valve body 105. Leads to. In order to maintain the valve-closing response, it is necessary to increase the amount of electric power supplied to the coil 106 or increase the physical size to increase the attraction force of the solenoid valve 103. This increases the power cost and manufacturing cost of the solenoid valve. There was a problem of inviting.

In the variable discharge high-pressure pump having the above-described structure, the opening and closing of the low-pressure passage 104 to the pressure chamber 102 is controlled by the solenoid valve 1.
03, it takes a certain time for the valve body 105 to seat and close the low-pressure flow path 104 in response to the valve-closing signal. Is controlling. However, when the rotation speed of the engine increases and the oil supply rate of the pump increases, the opening and closing operation may not be performed in time, and sufficient control may not be performed.

Therefore, the present inventors have made it possible to easily and reliably control the flow rate of the pressure supplied to the common morail even when the engine speed is increased and the oil supply rate of the pump is high, and to increase the size of the apparatus and increase the electric power. For the purpose of not involving
We have proposed a variable discharge high pressure pump in which a valve body that opens and closes between the low pressure flow path and the pressure chamber and a valve body that controls the flow rate of the low pressure fuel sucked into the pressure chamber from the low pressure flow path are separately provided ( Japanese Patent Application No. 9-100939).

Referring to FIG. 22, a drive shaft 111 is inserted and held in a pump housing 110, and a low-pressure fuel is supplied to a low-pressure passage 1 by a feed pump 112 which rotates integrally with the drive shaft 111.
The fuel flows into the fuel reservoir 115 from 13 and 114.

At the right end of the drive shaft 111, an inner cam 116 is formed integrally, and the left end of the head 117 is inserted into the inner cam 116. In the left end of the head 117, four cylinders 1
18 are formed radially (only two of them are shown), and a plunger 119 is supported in each cylinder 118 so as to be able to reciprocate. A pressure chamber 120 is formed by the inner end surface of the plunger 119 and the inner wall of the cylinder 118, and pressurizes the introduced fuel by reciprocating the plunger 119.

In the flow path from the fuel reservoir 115 to the pressure chamber 120, an electromagnetic valve 121 for flow control and a check valve 122 are provided from the upstream side. The check valve 122 is opened by the pressure of the inflowing fuel while the solenoid valve 121 is open, and is closed when the solenoid valve 121 is closed. When the necessary amount of fuel is supplied into the pressure chamber 120 in advance by the solenoid valve 121, the flow path to the pressure chamber 120 is closed by the check valve 122 from the start of pressurization of the low-pressure fuel to the end of the pumping. Only the feed pressure (about 15 atm) acts on the solenoid valve 121 even at the maximum pressure. Therefore, there is no need to increase the size of the solenoid valve 121, and the cost can be reduced.

However, the variable discharge amount high pressure pump has a structure in which the four plungers 119 reciprocate simultaneously to pressurize the fuel in the pressure chamber 120, and the driving torque required for the pressurized fuel pressure feed is provided. Is big. FIG. 23 (A)
Indicates the maximum drive torque (drive torque at the maximum discharge amount) when the four plungers 119 and four cam ridges are formed on the inner peripheral surface of the inner cam 116 in the variable discharge high-pressure pump having the above configuration. It is a thing. The pumping is performed four times per rotation of the inner cam 116, that is, the drive shaft 111, and the pumping is performed intermittently at a pumping period of about 45 ° and a suction period of about 45 °. At this time,
The maximum driving torque is 50 Nm.

On the other hand, in order to rotationally drive the inner cam 116 and the drive shaft 111 integrated therewith,
Usually, a timing belt is used. As shown in FIG. 22, a pump timing pulley 123 is fixed to the left end portion of the drive shaft 111, and the rotational force of the engine is transmitted to the inner cam 116 by a timing belt (not shown) suspended around the outer periphery thereof. Drive.
However, as described above, the maximum driving torque is 50 Nm.
When the timing belt is large, the load applied to the timing belt is large, and the durability may be reduced.

Therefore, the present inventors further provided a plurality of pressure chambers, and provided a means for supplying low-pressure fuel to each of these pressure chambers, so that the plurality of pressure chambers were alternately pressurized and pressure-fed. Fig. 23 proposes a variable discharge high pressure pump.
The maximum driving torque was reduced as shown in FIG.
The solid line indicates the driving torque for expanding and contracting one pressure chamber, and the broken line indicates the driving torque for expanding and contracting the other pressure chamber. The sum of the two driving torques is the necessary driving torque. Furthermore, based on the configuration of FIG. 22, one solenoid valve for adjusting the suction amount of low-pressure fuel into the pressure chamber is provided for each pressure chamber, and the metering characteristic in a region where the oil supply rate is low is provided. The improvement was also proposed.

[0016]

However, in the case where one solenoid valve is provided for each pressure chamber as described above,
The amount of low-pressure fuel sucked into the pressure chambers differs between the pressure chambers due to the individual responsiveness to the drive signal of the solenoid valve, particularly the responsiveness when the valve is closed. Therefore, there has been a problem that the discharge amount of the high-pressure fuel discharged from the variable discharge amount high-pressure pump fluctuates and the pressure of the common rail oscillates.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a common rail type fuel injection control device in which the discharge amount of the high pressure fuel discharged from the variable discharge amount high pressure pump is constant and the pressure of the common rail is constant.

[0018]

According to the first aspect of the present invention, a common rail type fuel injection control device includes: a common rail for supplying high pressure fuel to an electromagnetic fuel injection valve for injecting fuel into each cylinder of an internal combustion engine; And a variable discharge high pressure pump for pumping high pressure fuel. The variable discharge high-pressure pump is provided in a pressure chamber in which the volume is expanded and contracted to introduce fuel and feed the introduced fuel to a common rail, and an introduction passage for introducing fuel into the pressure chamber, and opens and closes the same. Equipped with a solenoid valve to control the amount of fuel introduced into the pressure chamber,
The discharge amount of fuel to the common rail is variable. The common rail type fuel injection control device further comprises control means for outputting a valve opening signal and a valve closing signal to the solenoid valve to adjust the discharge amount of the variable discharge amount high pressure pump, and controlling the common rail fuel pressure to a predetermined pressure. To control. The variable discharge high pressure pump has a configuration in which a plurality of the pressure chambers are provided therein, the electromagnetic valves are provided for each of the pressure chambers, and timings at which the volumes of the pressure chambers expand and contract are mutually shifted. The control means includes a storage means for storing in advance a time delay of the solenoid valve from the time of outputting the valve closing signal to the closing of the solenoid valve, and based on the time delay stored in the storage means. The output timing of the valve closing signal is corrected.

Since a plurality of pressure chambers are provided and the timings at which the volumes of the pressure chambers expand and contract are shifted from each other, an excessive driving torque is not required. In addition, the electromagnetic valve that controls the amount of fuel introduced into the pressure chamber corrects the output timing of the valve closing signal based on the time delay, thereby canceling out the variation of the time delay between individual electromagnetic valves, The difference between the desired and the actual pumping amount of fuel no longer varies between the pressure chambers. Thus, the fluctuation of the common rail pressure is suppressed.

According to a second aspect of the present invention, there is provided a common rail type fuel injection control device which supplies high pressure fuel to an electromagnetic fuel injection valve which injects fuel into each cylinder of an internal combustion engine, and pressure feeds high pressure fuel to the common rail. And a variable discharge high pressure pump. The variable discharge high-pressure pump is provided in a pressure chamber in which the volume is expanded and contracted to introduce fuel and feed the introduced fuel to a common rail, and an introduction passage for introducing fuel into the pressure chamber, and opens and closes the same. An electromagnetic valve for controlling the amount of fuel introduced into the pressure chamber is provided, and the amount of fuel discharged to the common rail is made variable. The common rail type fuel injection control device further comprises control means for outputting a valve opening signal and a valve closing signal to the solenoid valve to adjust the discharge amount of the variable discharge amount high pressure pump, and controlling the common rail fuel pressure to a predetermined pressure. To control. The variable discharge high pressure pump has a configuration in which a plurality of the pressure chambers are provided therein, the electromagnetic valves are provided for each of the pressure chambers, and timings at which the volumes of the pressure chambers expand and contract are mutually shifted. The control means includes a storage means for storing in advance the difference between the time delay of the solenoid valve from the time of outputting the valve closing signal to the closing of the solenoid valve and the time delay of the other solenoid valves. The output timing of the valve closing signal is corrected based on the time delay difference stored in the means.

Since a plurality of pressure chambers are provided and the timings at which the volumes of the pressure chambers expand and contract are shifted from each other, an excessive driving torque is not required. In addition, the solenoid valve that controls the amount of fuel introduced into the pressure chamber corrects the output timing of the valve-closing signal based on the difference in the time delay, thereby offsetting the variation in the time delay between individual solenoid valves. The difference between the expected and the actual pumping amount of fuel no longer varies between the pressure chambers. Thus, the fluctuation of the common rail pressure is suppressed.

[0022]

FIG. 1 shows an embodiment of a common rail fuel injection control device according to the present invention. In FIG. 1, an engine E is provided with a plurality of electromagnetic fuel injection valves I corresponding to the combustion chambers of the respective cylinders. These electromagnetic fuel injection valves I are connected to a common rail R common to the respective cylinders. Is supplied with high-pressure fuel.
In the common rail R, supply pipe R1, delivery valve 3
And a variable discharge high-pressure pump P is connected through the common rail R, and a high predetermined pressure fuel corresponding to the fuel injection pressure is continuously accumulated in the common rail R. The variable discharge high pressure pump P pressurizes the fuel sucked from the fuel tank T via the feed pump P1 to a high pressure and supplies the fuel into the common rail R.

The electronic control unit ECU that controls the fuel injection system receives detection signals from various sensors, and receives signals from, for example, an engine rotation angle sensor S2 and a load sensor S3.
The electronic control unit ECU determines the optimum injection timing and injection amount (injection period) according to the engine state determined by these signals, and inputs the information of the engine rotation angle and the load. , And the electromagnetic fuel injection valve I injects fuel in the combustion chamber based on the control signal. The electronic control unit ECU has:
A detection signal of a common rail pressure is input from a pressure sensor S1 provided in the common rail R, and the electronic control unit E
The CU controls the discharge amount so that the common rail pressure becomes an optimum value set in advance according to the load and the rotation angle.

Further, in the present invention, correction resistors 95a and 95b as storage means constituting control means together with the electronic control unit ECU, which will be described in detail later, are provided. The resistance values of the correction resistors 95a and 95b are selected according to the characteristics of the individual solenoid valves 6a and 6b that control the discharge amount of the variable discharge amount high pressure pump. The correction resistors 95a and 95b are desirably attached to the variable discharge high pressure pump P to which the solenoid valves 6a and 6b are attached.

A cylinder discrimination signal is input from the cylinder discrimination sensor S4 to the electronic control unit ECU.

Next, the details of the variable discharge amount high pressure pump P will be described with reference to FIGS. FIG. 2 shows an entire vertical cross section of the variable discharge high pressure pump P, and FIG. 3 shows an enlarged cross section of a main part thereof. In the pump housing 1, a drive shaft D, which is rotationally driven by the engine in synchronization with half the rotation of the engine, is inserted and held. At the left end of the drive shaft D, there is a pump timing pulley 5
1 is fixed and, as shown in FIG. 4, is driven to rotate by a timing belt 52 suspended around its outer periphery. In the figure, a camshaft timing pulley 53 is fixed to a camshaft (not shown) of the engine, and a crankshaft timing pulley 54 is fixed to the crankshaft. And the camshaft timing pulley 53 is rotationally driven. Reference numerals 55 and 56 in the drawing denote idlers. Of these, the idler 56 has a function of imparting tension to the timing belt 52 by the spring force of the spring 57 to prevent deflection.

2 and 3, the drive shaft D
Is connected to a vane-type feed pump P1 for supplying low-pressure fuel. The feed pump P1 rotates integrally with the drive shaft D, and sucks the fuel from the fuel tank T (FIG. 1) to pressurize the fuel to a low pressure. The fuel is fitted to the low-pressure channels 11 and 12 and the right end openings of the pump housing 1. The fuel is sent to the fuel pool 5 through the low-pressure channel 13 in the head 14.
In the fuel pool 5 of the head 14, there is a feed pump P1.
Is filled with low-pressure fuel pressurized to about 15 atm. The fuel discharge side and the fuel suction side of the feed pump P1 are connected via a pressure adjusting valve (not shown) so that the discharge pressure can be adjusted. As described above, in the present embodiment, the variable discharge amount high-pressure pump P is configured to include the feed pump P1.

The drive shaft D is rotatably held by the pump housing 1 via a bearing D2.
An inner cam 8 is integrally formed at the right end.
Although the drive shaft D and the inner cam 8 are integrated, they may be separated and connected by a joint. The head 14 is inserted into the inner cam 8 with its central left end protruding.

At the lower end of the head 14, an electromagnetic valve 6a is provided. A check valve 4a, which will be described in detail later, is provided in the center of the right end of the head 14. The delivery valve 3 is provided above the check valve 4a. A plurality of check valves and solenoid valves are provided, and another check valve 4b and another solenoid valve 6b (details will be described later) are provided at positions not shown.

The head 14 has a flow path 72 from the solenoid valve 6a to the check valve 4a, flow paths 30a and 40a from the check valve 4a to a pressure chamber 23a described later, and a delivery valve 3 from the flow path 40a. Is formed. A flow path 72 from the solenoid valve 6b to the check valve 4b, and flow paths 30b and 40b from the check valve 4b to a pressure chamber 23b to be described later are formed at positions not shown. The discharge hole 16b is a discharge hole extending from the flow path 40b to the delivery valve 3.

The solenoid valve 6a has a housing 61 containing a coil 62, and a valve body 68 fitted and fixed in the upper end thereof, and a cylinder 69 provided on the valve body 68.
The valve body 73 is slidably held therein. Solenoid valve 6a
Is fixed by inserting a bolt (not shown) through a flange 63 provided on the outer periphery of the housing 61. Valve element 7
An annular flow path 74a is formed around the upper end of 3 and the flow path 74a communicates with the fuel reservoir 5 through a flow path 74b and communicates with a flow path 72 reaching the check valve 4a through a flow path 74c. doing.

An armature 64 is press-fitted and fixed to the lower end of the valve body 73, and the armature 64 faces the stator 65. A coil 62 is disposed outside the stator 65, and a spring 67 is disposed in a spring chamber 66 provided inside the stator 65, and urges the armature 64 upward in the drawing.

A substantially conical seat surface 75 is formed at the open end of the flow passage 74c, and in the state shown in FIG. , 74c. When the coil 62 is energized, the armature 64 is attracted, and the distal end of the valve body 73 integrated therewith separates from the seat surface 75 and the flow path 7
Open between 4a and 74c. Thus, the solenoid valve 6a is
The configuration in which the valve is closed in a non-energized state has an effect of preventing the fuel from being pumped when the coil 62 fails. The electromagnetic valve 6b (not shown) has the same configuration.

At the center of the left end of the head 14, sliding holes 2a and 2b as a plurality of cylinders forming pressure chambers therein are formed. FIG. 5 (A) is a cross-sectional view of FIG.
A cross section taken along line A, and a pair of plungers 2
1a and 21c are arranged facing each other, and are supported reciprocally and slidably with respect to the sliding hole 2a. The space formed by the inner wall surface of the sliding hole 2a and the end surfaces of the plungers 21a and 21c is a pressure chamber 23a. FIG.
(B) is a cross-section along the line BB in FIG. 2 (and FIG. 3), and similarly, a pair of plungers 21
b and 21d are opposed to each other, and are reciprocally and slidably supported in the sliding holes 2b. Sliding hole 2
The space formed by the inner wall surface of b and the end surfaces of the plungers 21b and 21d is a pressure chamber 23b.

In the pair of plungers 21a and 21c, one plunger 21a is formed shorter than the other plunger 21c, and therefore, the pressure chamber 23a is formed in the sliding hole 2a.
It is located slightly off the center of. A pair of plungers 2
The same applies to 1b and 21d, in which the plunger 21d is shorter than the other plunger 21b, and the pressure chamber 23b is formed at a position slightly shifted from the center of the sliding hole 2b. By doing so, there is an advantage that the flow paths 30a and 40a are easily formed.

Further, shoes 24a, 24b, 24c and 24d are provided at the outer ends of the plungers 21a to 21d, and the cam rollers 22a and 2d are attached to the shoes 24a to 24d.
2b, 22c and 22d are held rotatably. The shoes 24 a to 24 d are slidably held at their end surfaces by a shoe guide 15 and a plate 7. The shoe guide 15 and the plate 7 are fixed to the head 14 by bolts (not shown). A washer 76 is inserted between the plate 7 and the drive shaft D, and between the drive shaft D and the washer 76, and between the washer 76 and the plate 7
It is designed to rotate and slide between them.

As described above, in the present embodiment, a plurality of sliding holes 2a and 2b independent of each other are provided, and these are arranged at intervals in the axial direction of the drive shaft D. 2a and 2b are formed such that their axes are orthogonal to each other. Also, the sliding holes 2a and 2b are
Each is formed in a direction orthogonal to the axis of the drive shaft D.

The inner cam 8 has a plurality of sliding holes 2a, 2
The plungers 21a to 21d are reciprocated in the sliding holes 2a and 2b by the rotation thereof. The inner peripheral surface of the inner cam 8 is a cam surface 81 having a plurality of cam ridges.
Are arranged so that the outer circumferences of the cam rollers 22a to 22d are in sliding contact with the cam rollers. Here, the inner peripheral surface of the inner cam 8 is formed in an elliptical shape, and two cam ridges are formed at equal intervals (FIG. 5).
(The position facing the plungers 21a and 21c in (A)).

When the inner cam 8 integrated with the drive shaft D rotates, the plungers 21a, 2a
1c reciprocates in the sliding hole 2a, and the plungers 21a and 21c alternately rise to pressurize the fuel in the pressure chamber 23a.

Here, in the present invention, the plungers 21a to 21a
The top 82 of the cam ridge of the inner cam 8 is formed in an arc shape centered on the cam center O so that the distance from the center O is constant so that 1d maintains the state of being at the maximum lift position for a certain period. (FIG. 6). At this time, the lift curve of the inner cam 8 is such that the top of the lift becomes flat (straight), and the plungers 21 a to 21 driven by the inner cam 8 are driven.
The same applies to the lift d. Therefore, plungers 21a-2
1d does not immediately start descending after reaching the maximum lift position, and holds this state while the inner cam 8 rotates by the angle θ. While the plungers 21a to 21d are at the maximum lift position, the fuel is not sucked in. During this time, the solenoid valves 6a and 6b are controlled so that the opening of the solenoid valves 6a and 6b is completed. The effects of valve-to-individual variability are eliminated. Note that this angle θ differs depending on the maximum engine speed, and is usually appropriately selected in the range of 20 to 40 °. In the present embodiment, θ = 30 °.

FIG. 7 shows the lift and cam speed of the inner cam in one cycle from the start of the pumping stroke to the start of the suction stroke. The cam speed is 0 during 30 ° from the end of the pumping stroke to the start of the suction stroke. Becomes During this time, the cam lift is flat.

In the present embodiment, the cam lift is flat in a section of 30 °, but the cam lift may be slightly lowered. At the end of pumping,
The pressure chamber has a high pressure of about 120 MPa (1200 atm), and the volume expands when the pressure drops to 1.5 MPa (15 atm), which is the feed pressure. This is because the fuel is not sucked into the pressure chamber even if it has a substantially flat shape such that the cam lift descends during the 30 ° section by the lift amount corresponding to the volume expansion.

The check valve 4a has a flow path 43 penetrating the housing 42 in the left-right direction, and a valve body 44 for opening and closing the flow path 43. The flow path 43 has a conical seat surface 45 formed in the middle of the flow path 43 in the direction of the pressure chamber 23a. Valve body 44
Is biased rightward by a spring 46 held in a spring stopper 41 and is seated on a seat surface 45. As described above, the check valve 4a is closed in the illustrated normal state, and when the low pressure fuel flows from the fuel reservoir 5 by opening the solenoid valve 6a, the check valve 4a is opened by the fuel pressure. . When the valve is opened, the low-pressure fuel is supplied to the flow paths 11, 12, and 13, the fuel pool 5, and the flow path 7 via the electromagnetic valve 6a.
2, an annular flow path 48 provided on the outer periphery of the housing 42, a flow path 49 inside the housing 42, a flow path 43, a flow path 50 in the spring stopper 41, and flow paths 30a and 40a of the head 14.
Through the pressure chamber 23a.

The structure of the check valve 4b not shown in FIGS. 2 and 3 is the same as that of the check valve 4a. These check valves 4a,
4b is fixed in the head 14 by a screw 47.

The delivery valve 3 includes pressure chambers 23a, 23
b is a check valve whose forward direction is a direction in which fuel flows into the delivery valve 3 from b.
b. The ball 31a is configured to open and close a flow path following the discharge hole 16a communicating with the pressure chamber 23a, and the ball 31b is configured to open and close a flow path following the discharge hole 16b communicating with the pressure chamber 23b (FIG. 5).

As shown in FIG. 8, in the present embodiment, two plungers 21a and 21c, 21b and 21d are respectively disposed in two independent sliding holes 2a and 2b, and A pressure chamber 23a surrounded by a pair of plungers 21a and 21c and a pressure chamber 23b surrounded by a sliding hole 2b and a pair of plungers 21b and 21d are alternately expanded and contracted to introduce and pressurize low-pressure fuel. And do. Pressure chamber 23
a is located on the ball 31a side of the delivery valve 3 through the flow path 40a and the discharge hole 16a.
b, through the discharge hole 16b, communicates with the ball 31b side of the delivery valve 3 respectively. Each pressure chamber 23a, 2
When the pressure of the fuel pressurized at 3b becomes higher than the pressure of the common rail R, these balls 31a or 31
b opens and is supplied to the common rail R. The supply pressure varies depending on the operating state of the engine E,
200 atm. Here, since the pressurization of the fuel in the pressure chambers 23a and 23b is performed alternately, the balls 31a and 3b
The discharge of fuel via 1b is also performed alternately.

The suction amount (introduction amount) of low-pressure fuel into the pressure chambers 23a and 23b is defined by the closing timing of the solenoid valves 6a and 6b. As described above, the low-pressure channels 11, 12, 1
3, an introduction path is formed by the flow paths 30a, 40a, 30b, 40b, 72, the fuel pool 5, and the like.

Next, a control system centered on the electronic control unit ECU will be described. FIG. 9 is a configuration diagram of such a control system.

A signal rotor 17 shown in FIG. 10 is mounted on the engine E coaxially with the drive shaft D, and an engine rotation angle sensor S2 is provided at a position facing the outer peripheral surface of the signal rotor 17. I have. 56 protrusions 18 are formed on the outer peripheral surface of the signal rotor 17 except for four missing tooth portions that divide the outer peripheral surface into four equal parts. The 14 projections 18 form a group, and the interval between the projections 18 is 5.625 °. Engine rotation angle sensor S
2 generates a detection signal each time these projections 18 cross and outputs the detection signal to the electronic control unit ECU (FIG. 1). At this time, a detection signal is output from the rotation angle sensor S2 as shown in FIG. 11, and the waveform is shaped by the waveform shaping circuit 91 of the electronic control unit ECU, so that the fuel injection cycle and The synchronized reference signal A and rotation angle signal B are obtained.

On the other hand, the electronic control unit ECU (FIG. 9)
Has an A / D converter 92 that converts analog signals output from the pressure sensor S1, the load sensor S3, the cooling water temperature sensor S5, the intake air temperature sensor S6, and the intake pressure sensor S7 into digital signals.

The CPU 90 determines the electromagnetic fuel based on the rotation angle signal of the rotation angle sensor S2 input through the A / D converter 92 or the waveform shaping circuit 91 and the cylinder discrimination signal input from the cylinder discrimination sensor S4. Injection valve I, solenoid valve 6
The control of a and 6b is executed. Electronic control unit ECU
Is an R in which a control program and various data necessary for executing a control process by the CPU 90 are stored in advance.
The OM 96 includes a RAM 97 for temporarily reading and writing data necessary for executing control processing by the CPU 90, and drive circuits 99a and 99b for outputting drive signals to the electromagnetic fuel injection valve I and the electromagnetic valves 6a and 6b, respectively. ing. In FIG. 9, although not shown, the electromagnetic fuel injection valve I and its drive circuit 98 are provided for the number of cylinders of the engine.

FIG. 12 shows that the drive circuit 99
a, the drive signal output to 99b, the solenoid valve 6
a, 6b, current flowing through coil 62, solenoid valves 6a, 6b
3 shows the displacement of the valve body 73 of FIG. Drive signal is ON (valve open signal)
After that, the time delay (opening time) of the solenoid valves 6a and 6b until the valve element 73 closes is 1.5 ms, and the variation among the solenoid valves is ± 0.1 ms. In the present embodiment, control is performed such that the opening of the solenoid valve ends at the flat top of the lift curve (a detailed flowchart will be described later).

The drive signal shown in FIG. 12 is off (valve closing signal).
The time delay (valve closing time) of the solenoid valves 6a and 6b until the valve body 73 closes is 1.0 ms.
The variation between the solenoid valves is ± 0.1 ms, and the end time of energization to the coil 62 is corrected by the control method described later so that the variation in the valve closing time between the individuals cancels out. The difference between the suction amount of the pressure chamber and the actual suction amount is the pressure chamber 23a,
The difference is not generated between 23b.

The correction resistors 95a and 95b are connected to the individual solenoid valves 6
The correction amounts of the power supply end times a and 6b are stored. The correction amounts are measured in advance and stored as resistance values of the correction resistors 95a and 95b. The A / D converter 92 has 5
The voltage between the V potential terminal 93 and the ground potential terminal 94 is corrected by a correction resistor 95a and a resistor 95 provided inside the electronic control unit ECU.
c, a voltage Va divided by a correction resistor 95b and a resistor 95d provided inside the electronic control unit ECU.
b is input, and the resistance values of the correction resistors 95a and 95b are set as voltages Va and Vb proportional thereto, and the A / D converter 92
Through the CPU 90.
Note that the correction resistors 95a and 95b and the resistors 95c and 95d may change depending on the temperature of the installation environment.
b, the resistors 95c and 95d are preferably provided with a temperature compensation resistor.

Next, a control routine executed by the CPU 90 will be described with reference to FIGS. FIG.
FIG. 14 shows N executed by the CPU 90 every time a NE pulse signal is output from the engine rotation angle sensor S2.
This indicates E-pulse signal interrupt processing. When the processing is started, first, in step 201, the time from when the previous interrupt processing was executed to when the current interrupt processing is executed,
That is, the pulse interval Tp of the rotation angle signal is calculated.

Next, in step 202, the pulse interval Tp (n) obtained in step 201 is compared with a value obtained by multiplying the pulse interval Tp (n-1) obtained in the previous processing by a constant K. Thus, it is determined whether or not the rotation angle signal input this time is a reference signal. This is because when the reference signal is input, the pulse interval Tp during that time becomes a value that is about 2.5 times larger than usual, so that, for example, the constant K
Is set to 2.28, which is slightly smaller than 2.5, and the pulse interval T
p (n) is K with respect to the previous pulse interval Tp (n-1).
If it is twice or more, it can be detected that the current rotation angle signal is a reference signal (see FIG. 10) which is a pulse immediately after crossing the toothless portion of the signal rotor 17. If it is determined in step 202 that the current rotation angle signal is not the reference signal, the process proceeds to step 203.

At step 203, the value of the NE pulse signal number (NE pulse number) C is increased by one, and the routine proceeds to the next step 204. The NE pulse number C has a reference signal C = 0, and is sequentially assigned from 1 to 13. The process of step 204 is performed by controlling the drive signal of the solenoid valve 6a or the solenoid valve 6
This is a process for detecting whether it is a timing to set the off time of the drive signal b. If C = C0 is not satisfied, it is determined that the timing is not the same, and step 212
Proceed to.

The process of step 212 is a process for detecting whether it is a timing to turn on the drive signal of the solenoid valve 6a or the drive signal of the solenoid valve 6b, and when the NE pulse number is the last NE pulse number. (C = 13) is the timing at which the drive signal is turned on. C ≠ 1
In the case of 3, it is determined that it is not the timing, and the processing of this routine is terminated as it is. On the other hand, if it is determined in step 212 that C = 13, the process proceeds to step 213.

In the next step 213, it is determined whether or not F1 = 1. When it is determined that F1 = 1, that is, when it is the timing to drive the solenoid valve 6a, the routine proceeds to step 214, where the drive signal of the solenoid valve 6a is turned on, and the processing of this routine ends. On the other hand, when it is determined in step 213 that F1 ≠ 1, the routine proceeds to step 215, where the drive signal of the solenoid valve 6b is turned on, and the processing of this routine is ended.

On the other hand, if it is determined in step 202 that the rotation angle signal is a reference signal,
Proceed to 6. The procedure following step 216 is a step of setting the fuel injection period and the like. In step 216, NE
The value of the pulse signal C is set to 0. Then, the routine proceeds to step 217, where the engine speed N is calculated, and then the routine proceeds to step 218.

Next, in step 218, various detection signals indicating the operating state of the engine E and the voltages Va and Vb output from the load sensor S3, the cooling water temperature sensor S5, the intake air temperature sensor S6, and the intake pressure sensor S7 are read. Proceed to 219.

In the next step 219, the flag F1 is set based on the cylinder discrimination signal from the cylinder discrimination sensor S4. The output of the cylinder discriminating sensor S4 is 5V when the solenoid valve 6a is driven, and is 0V when the solenoid valve 6b is driven. When the output of the cylinder discriminating sensor S4 is 5V, F1 is set to one. And the cylinder discrimination sensor S
When the output of 4 is 0 V, F1 is set to 0 and the routine proceeds to the next step 220.

In step 220, the target common rail pressure is calculated based on the engine speed and various detection signals which are read in step 218 and indicate the operating state of the engine E. That is, the engine speed N and the load sensor S
The basic target common rail pressure is calculated using the accelerator pedal depression amount calculated in step 3 as a parameter, and the obtained value is then used as the cooling water temperature THV,
The target common rail pressure is determined by correcting with the intake air temperature Ta, the intake pressure Pa and the like.

In the next step 221, the pressure sensor S1
Then, the output detection signal is read to calculate the actual common rail pressure. In step 222, the target common rail pressure calculated in step 220 is compared with the actual common rail pressure calculated in step 221 to calculate an error in the common rail pressure, and the process proceeds to step 223. Step 2
In 23, the energization end angle of the solenoid valve 6a is calculated when the solenoid valve 6a is driven, and the energization end angle of the solenoid valve 6b is calculated when the solenoid valve 6b is driven, based on the common rail pressure error. Here, the energization end angle is set on the retard side as the actual common rail pressure is lower than the target common rail pressure, so that the opening time of the solenoid valve 6a or 6b is lengthened to increase the common rail pressure.

In the next step 224, step 223
From the energization end angle calculated by
Calculate 0 and the remaining time t. The energization end NE pulse number C0 is the NE that corresponds to the energization end time as shown in FIG.
In the NE pulse number of the pulse, the remaining time t is the time from the rise of the NE pulse to the end of energization. That is, in the illustrated example, when the energization end angle = 33.1 °, the energization end NE pulse number C0 = 5, and the surplus angle 4.9.
The remaining time t corresponding to 75 ° is calculated according to the engine speed N.

Steps 225 to 227 and steps 205 and 206, which will be described later, are provided to prevent the CPU from performing normal processing due to multiple interrupts when the remaining time t is too short.

In step 225, the remaining time t> 0.5
ms, and if it is determined that t> 0.5 ms, the routine proceeds to step 227, where the flag F2 is set to 0.
And the process of this routine is terminated. On the other hand, when it is determined in step 225 that t> 0.5 ms is not satisfied, the process proceeds to step 226, and the energization end NE pulse number C
The value of 0 is decreased by 1 and the flag F2 is set to 1
And the processing of this routine is terminated. Flag F
A flag 2 indicates whether step 226 has been performed, that is, whether the C0 value has been reduced by one.

On the other hand, in step 204, C = C0
That is, the drive signal of the solenoid valve 6a or the solenoid valve 6
If it is determined that it is time to set the off time of the drive signal b, the process proceeds to step 205. Step 2
At 05, it is determined whether or not step 226 has been executed based on the flag F2. If F2 = 1, step 206 is executed and it is determined that the energization end NE pulse number C0 has decreased by one, and the routine proceeds to step 226, where the pulse interval tp is added to the remaining time t, and the routine proceeds to step 207. On the other hand, when it is determined in step 205 that F2 is not 1, the flow directly proceeds to step 207.

In the next step 207, it is determined whether or not F1 = 1. If it is determined that F1 = 1, that is, it is the timing to drive the solenoid valve 6a, the process proceeds to step 208.

In step 208, step 224 (2
The remaining time t calculated in step 06) is corrected. The correction time is determined according to the read voltage Va. FIG. 16 shows the relationship between the voltage Va and the correction time. The correction resistor 95a is selected so that the voltage Va corresponds to the correction time required for the solenoid valve 6a. Therefore, in the present step 208, a correction is made to add or subtract the remaining time t by the correction time shown in FIG. 16 using the voltage Va read in step 218.

The resistance 95c of FIG. 9 is 1 kΩ, and the correction resistance 95a is 0.25 kΩ according to the closing time of the solenoid valve 6a.
４4 kΩ, and the voltage Va takes a value in the range of 1 V to 4 V. Here, when the closing time of the solenoid valve 6a is a standard value, the correction resistance 1 kΩ is selected, and the voltage Va becomes 2.5V. As the closing time of the solenoid valve 6a is shorter, the correction resistance 95
For a, a resistor having a larger resistance value exceeding 1 kΩ is selected to increase the voltage Va.

In step 209, the time when the drive signal of the solenoid valve 6a is turned off, that is, the energization end time, is set, and the processing of this routine ends.

On the other hand, when it is determined in step 207 that F1 ≠ 1, that is, the timing for driving the solenoid valve 6b, the process proceeds to step 210.

At step 210, the remaining time t for the solenoid valve 6b is determined at step 20 based on the voltage Vb.
The same correction as in step 8 is performed, and the process proceeds to step 211

Then, at step 211, the energization end time of the solenoid valve 6b is set, and the processing of this routine ends.

Next, the operation of the common rail type fuel injection control device having the above configuration will be described with reference to FIG.

In the figure, at time (a), the pressure chamber 23
a, the operation of the inner cam 8 for the plungers 21a and 21c is indicated by (a, c), and the operation of the inner cam 8 for the plungers 21b and 21d is indicated by (b, d). ) Is finished, and in the NE pulse signal interruption processing when the NE pulse number C = 13, the step 21 in FIG.
The drive signal of the solenoid valve 6a is turned on by 4 to energize the coil 62 of the solenoid valve 6a. From the start of energization of the coil 62 to the opening of the valve body 73, it takes about 1.5 ms as described above. On the other hand, the lift curve of the inner cam 8 has a flat top at 30 °, but in this embodiment, the maximum rotation speed of the variable discharge high pressure pump is 250
0 rpm, at which time an angle of 30 ° corresponds to 2 ms. Then, between its flat tops, the solenoid valve 6
Regardless of the variation in the valve opening time a, the valve element 73 is completely opened.

At the point (b), the inner cam 8 (a, c)
Enters the suction stroke, and fuel flows from the fuel reservoir 5a into the pressure chamber 2
3a. At this time, the plungers 21a and 21c are lowered by being pressed against the cam surface 81 by the inflowing fuel, and the fuel is sucked until the valve body 73 of the electromagnetic valve 6a is closed.

When the energization of the coil 62 of the solenoid valve 6a from the drive circuit 99a is interrupted, the valve body 73 of the solenoid valve 6a
Is closed (point (c)), and the suction of fuel into the pressure chamber 23a ends. Thereafter, the lift of the inner cam 8 (a,
c) continues to descend, but the lift of the plungers 21a, 21c stops, and the cam rollers 22a, 22c and the inner cam 8 separate.

At the point (d) in the figure, the lift (a, c) of the inner cam 8 starts to rise and enters the pressure feeding stroke. Even if the lift (a, c) of the inner cam 8 starts, the plunger 21
When the lift amounts of the points 81a and 81c on the cam surface 81 of the inner cam 8 become the lift amounts of the plungers 21a and 21c (point (f) in FIG. 17), the cam rollers a and 21c do not immediately start the lift. 22a, 22c abut against the inner cam 8 (a, c), and the cam rollers 22a, 22c are moved through the shoes 24a, 24c to form the plungers 21a, 21c.
Lift. During this pumping stroke, the check valve 4
a is closed. Then, the plungers 21a and 21c
As the pressure rises, the volume of the pressure chamber 23 decreases, and the pressure chamber 2
The fuel pressure in 3 gradually increases. When the fuel pressure exceeds a predetermined pressure, high-pressure fuel is supplied from the supply pipe R1 to the common rail R via the discharge hole 16a and the delivery valve 3 (FIG. 1). When the lift of the plungers 21a and 21c becomes maximum (point (g) in FIG. 17), the pressure feeding ends.

During this time, at a point (e) in FIG. 17, the valve body 73 of the solenoid valve 6b is opened, and the inner cam 8 (b, d) is opened.
Enters the suction stroke. Thereafter, as in the case of the plungers 21a, 21c, the plungers 21b, 21d are lifted, and the fuel is sucked into the pressure chamber 23b. In this manner, two cam ridges are formed at equal intervals on the inner peripheral surface of the inner cam 8 so that the pair of plungers 21a and 21c and the pair of plungers 21b and 21d are alternately pressure-fed to maximize the maximum. The torque can be more effectively reduced, and the influence on the durability and the like of the timing belt 52 can be reduced.

In this embodiment, the solenoid valves 6a, 6b
The remaining time t, that is, the energization end time, is corrected in accordance with the valve closing time, so that the lift amounts of the plungers 21a and 21c and the plungers 21b and 21 when the valve body 73 closes.
The lift amount d is equal under the same engine condition. Therefore, the discharge amount of the variable discharge amount high pressure pump does not fluctuate alternately.

FIG. 1 shows a second embodiment of the present invention.
This will be described with reference to FIGS. In the figure, the portions denoted by the same reference numerals as in FIGS. 9, 13 and 14 perform substantially the same operation, and therefore, the description will be focused on the differences from the first embodiment.

In FIG. 18, there is only one correction resistor 95e. The voltage between the 5V potential terminal 93 and the ground potential terminal 94 is divided by the correction resistor 95e and the resistor 95f inside the electronic control unit ECU. Pressed voltage Vab is A / D
Input to the converter.

In step 218a of FIG. 20, the load sensor S3, the cooling water temperature sensor S5, and the intake air temperature sensor S
6. Read the various detection signals and the voltage Vab, which are output from the intake pressure sensor S7 and indicate the operating state of the engine E,
Proceed to step 219.

In step 207, it is determined whether or not F1 = 1. When F1 = 1, that is, when it is determined that it is time to drive the solenoid valve 6a, the process proceeds to step 209 without correcting the extra time t, and the process proceeds to step 209.
Then, the time when the drive signal is turned off, that is, the energization end time, is set, and the routine ends.

On the other hand, when it is determined in step 207 that F1 ≠ 1, that is, the timing for driving the solenoid valve 6b, the process proceeds to step 210a.

In step 210a, step 224
The remaining time t calculated in (206) is corrected. FIG.
The resistance 95f is 1 kΩ, and the correction resistance 95e is 0.25 according to the difference in the closing time between the solenoid valves 6a and 6b.
Values between kΩ and 4 kΩ are selected. If the valve closing time is the same between the solenoid valve 6a and the solenoid valve 6b, the correction resistor 95e selects 1 kΩ and the voltage Vab becomes 2.5V.

As the closing time of the solenoid valve 6b is shorter than the closing time of the solenoid valve 6a, the correction resistor 95e has a resistance value of 1 k.
A large value exceeding Ω is selected to increase the voltage Vab. FIG. 16 Based on the relationship between the NO pressure Vab and the correction time, the correction resistor 95e is selected so that the voltage Vab corresponds to the correction time required for the solenoid valve 6b. Therefore, in the present step 210a, the remaining time t is corrected by the correction time shown in FIG. 16 by the voltage Vab read in step 218a.

In this embodiment, the solenoid valve 6b is controlled according to the difference between the closing time of the solenoid valve 6b and the closing time of the solenoid valve 6a.
Is corrected, the lift amounts of the plungers 21a and 21c and the lift amounts of the plungers 21b and 21d when the valve body 73 closes are the same if the state of the engine is the same. equal. Therefore, the discharge amount of the variable discharge amount high pressure pump does not fluctuate alternately.

Although the discharge amount from the variable discharge amount high pressure pump changes depending on the closing time of the solenoid valve 6a, in steps 220 to 223, the energization end angle is calculated according to the common rail pressure. Therefore, feedback is applied in that step, and the target common rail pressure can be controlled.

The present embodiment has an advantage that the number of correction resistors can be reduced as compared with the first embodiment.

In this embodiment, the correction resistor is used. However, the ROM in which the closing time of the solenoid valve is recorded may be attached to the variable discharge high pressure pump to perform the correction. However, the variation in the discharge amount of the variable discharge amount high pressure pump differs from the fuel injection pump in that the closing time of the solenoid valve is dominant. Therefore, it is desirable to use an inexpensive resistor as in the present embodiment.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a common rail fuel injection control device of the present invention.

FIG. 2 is an overall sectional view of a variable discharge high-pressure pump constituting the common rail fuel injection control device of the present invention.

FIG. 3 is an enlarged sectional view of a main part of a variable discharge high pressure pump constituting the common rail fuel injection control device of the present invention.

FIG. 4 is a diagram showing a drive system of a variable discharge high pressure pump constituting the common rail fuel injection control device of the present invention.

5A is a sectional view taken along line AA in FIG. 2, and FIG. 5B is a sectional view taken along line BB in FIG.

FIG. 6 is a partial cross-sectional view of the inner cam of the variable discharge high-pressure pump constituting the common rail fuel injection control device of the present invention.

FIG. 7 is a time chart for explaining the operation of the variable discharge high pressure pump constituting the common rail fuel injection control device of the present invention.

FIG. 8 is a configuration diagram of a variable discharge amount high pressure pump that constitutes the common rail type fuel injection control device of the present invention.

FIG. 9 is a configuration diagram of a control system of the common rail fuel injection control device of the present invention.

FIG. 10 is a diagram illustrating a control system of the common rail fuel injection control device according to the present invention.

FIG. 11 is a first time chart illustrating the operation of the common rail fuel injection control device of the present invention.

FIG. 12 is a second time chart explaining the operation of the common rail fuel injection control device of the present invention.

FIG. 13 is a first flowchart illustrating the operation of the common rail fuel injection control device according to the present invention.

FIG. 14 is a second flowchart illustrating the operation of the common rail fuel injection control device according to the present invention.

FIG. 15 is a third time chart illustrating the operation of the common rail fuel injection control device of the present invention.

FIG. 16 is a graph illustrating the operation of the common rail fuel injection control device of the present invention.

FIG. 17 is a fourth time chart illustrating the operation of the common rail fuel injection control device of the present invention.

FIG. 18 is a configuration diagram of a control system of another common rail type fuel injection control device of the present invention.

FIG. 19 is a first flowchart illustrating the operation of another common rail fuel injection control device according to the present invention.

FIG. 20 is a second flowchart illustrating the operation of another common rail fuel injection control device according to the present invention.

FIG. 21 is a sectional view of a main part of a variable discharge high pressure pump of a conventional common rail type fuel injection control device.

FIG. 22 is an overall cross-sectional view of a variable discharge high-pressure pump constituting another conventional common rail fuel injection control device.

FIG. 23A is a time chart illustrating the operation of a conventional common rail fuel injection control device, and FIG. 23B is a time chart illustrating the operation of another conventional common rail fuel injection control device.

[Explanation of symbols]

11, 12, 13, 30a, 40a, 30b, 40b,
72 Flow path (introduction path) 5 Fuel reservoir (introduction path) 23a, 23b Pressure chamber 6a, 6b Solenoid valve 95a, 95b, 95e Correction resistance (storage means) ECU Electronic control unit (control means) I Electromagnetic fuel injection valve R Common rail P variable discharge high pressure pump

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Showa Kojima 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture Inside DENSO Corporation

Claims (2)

[Claims] 1. A common rail for supplying high-pressure fuel to an electromagnetic fuel injection valve for injecting fuel into each cylinder of an internal combustion engine, a fuel cell having a volume expanded and contracted, and fuel introduced and pressure-fed to the common rail. A pressure chamber and an introduction valve for introducing fuel into the pressure chamber, an electromagnetic valve for controlling the amount of fuel introduced into the pressure chamber by opening and closing the pressure chamber, and a variable amount of fuel discharged to the common rail. A discharge amount high pressure pump, and control means for adjusting the discharge amount of the variable discharge amount high pressure pump by outputting a valve opening signal and a valve closing signal to the solenoid valve, and controlling the fuel pressure of the common rail to a predetermined pressure. In the common rail type fuel injection control device, the variable discharge amount high pressure pump is provided with a plurality of the pressure chambers, the electromagnetic valve is provided for each pressure chamber, and a timing at which the volume of the pressure chamber expands and contracts. Are shifted from each other, and the control means is provided with storage means for storing in advance the time delay of the solenoid valve from when the valve closing signal is output to when the solenoid valve is closed, and in the storage means, A common rail fuel injection control device, wherein the output timing of a valve closing signal is corrected based on a stored time delay. 2. A common rail that supplies high-pressure fuel to an electromagnetic fuel injection valve that injects fuel into each cylinder of the internal combustion engine, a fuel cell whose capacity is expanded and reduced, and fuel introduced and pressure-fed to the common rail. A pressure chamber and an introduction valve for introducing fuel into the pressure chamber, an electromagnetic valve for controlling the amount of fuel introduced into the pressure chamber by opening and closing the pressure chamber, and a variable amount of fuel discharged to the common rail. A discharge amount high pressure pump, and control means for adjusting the discharge amount of the variable discharge amount high pressure pump by outputting a valve opening signal and a valve closing signal to the solenoid valve, and controlling the fuel pressure of the common rail to a predetermined pressure. In the common rail type fuel injection control device, the variable discharge amount high pressure pump is provided with a plurality of the pressure chambers, the electromagnetic valve is provided for each pressure chamber, and a timing at which the volume of the pressure chamber expands and contracts. Are shifted from each other, and the control means stores in advance a difference between a time delay of the solenoid valve from the time of outputting the closing signal to the closing of the solenoid valve and a time delay of another solenoid valve. Means for correcting the output timing of the valve closing signal based on the difference in the time delay stored in the storage means.